EPR - Disprove Uncertainty or Introduce Hidden Variables?

Question

Hi everyone,

I've just read Quantum - the Great Debate and thought I was doing fine until I came across Bell's theorem and had to question everything I understood from the beginning.

From the EPR what I understood was Einstein was proposing a method to actually measure both properties of an electron, position and momentum, by making indirect measurements. This in effect was disproving uncertainty.

However when I came to Bell's theorem it's discussing Hidden variables (offered by EPR) as opposed to "Spooky actions at a distance" by Bohr. Both of these cases are based on the absolute validity of the uncertainty principle.

Now what I don't understand is, I thought EPR paper was disproving uncertainty so if you already have a way of measuring both properties of a particle why would you need Hidden variables? Do they go from disproving uncertainty in one page to assuming uncertainty is correct so that they have to introduce hidden variables to make it stand on the next page?

Please clarify this to an average Joe :)

Answer 1

"From the EPR what I understood was Einstein was proposing a method to actually measure both properties of an electron, position and momentum, by making indirect measurements. This in effect was disproving uncertainty. "



I would disagree with this. I would say that what EPR is stating is not a method to do something, but pointing out the consequences of known behavior (namely measuring properties of entangled entities)



The point was that the logical conclusion to the explanation of QM at the time was that either there must be "hidden variables" to allow the entangled entity to have a specific information before the measurement, or for "spooky action at a distance" so the results of one measurement are communicated to the other.



Yes, they describe a method that could theoretically get around the uncertainty principle if it behaved in a classical manner. But it doesn't work and they knew it didn't work. They are instead making an argument that because it doesn't work that there is a problem with the QM description of the system.



EDIT:

Ah, I do not know which specific experiments would have been done at the time.



Yes, it's something like "because these two products have entangled properties and we can calculate the evolution of the system (sometimes via conservation of momentum, sometimes via other rules) we should be able to make measurement A on particle1 and measurement B on particle 2 and infer absolutely the state of the system at the time when particle 1 and 2 were interacting"



"Since we can't do that, there must be either hidden variables or faster-than-light communication. We don't like faster-than-light communication (due to relativity), so we think that hidden variables might be present".



Later experiments seem to disprove the idea of hidden variables being a possibility.

Answer 2

What a gaggle of horse dung! extremely! How does Heisenberg uncertainty concept (which form of states that when you pinpoint an electron as to the place that's you may no longer tell the place it is going and in case you be conscious of the place it is going you may no longer tell the place that's.) have something to do with the universe being undetermined and random? The uncertainty isn't that that is random or undetermined the uncertainty is which you won't be able to be conscious of the the place that's and the place it is going on an analogous time, yet those are the two parts which would be had at separate situations. how are you able to logically bounce from electrons to the universe? If what you're saying is authentic and electrons are random and hence the universe is then that randomness turns right into a trend and not something interior the universe ought to make any experience. like the improbability force on Zaphod's spaceship interior the Hitchhikers instruction manual if issues are extremely random then whales ought to be appearing in mid air and crashing to the earth. additionally your Schrodinger equation that's a quantum concept of ways a photon (easy waves) can function as a particle and a as a wave on an analogous time. alongside with this concept you have over a dozen greater that are contradictory to Schrodinger's and yet answer an analogous situation. So how does that disprove there's a God? It does not clarify the place the photons got here from interior the 1st place, it does not clarify the existence of self, will, morals, supernatural, etc. extremely throwing up this vomit is extremely undesirable. in basic terms by way of fact maximum Christians don't be conscious of quantum physics, and in case you published this you for sure do no longer the two.

Answer 3

Wikipedia has multiple articles in this area ... including experiments that have actually been conducted (whihc yield results in accordance to QT) some of which disprove 'hidden variables' ..



I suggest you look them up and then choose the 'solution' you like best ...(or, like most physicists, just avoid thinking about it, on the grounds that the closer you look at anything Quantum, the less certain you become :-) )





PS Personally I go for the -t 'answer' (I've never liked it when solutions to Maxwell's equations involving 'root(t squared) that 'resolve' into "+ or - t" are immediately followed by the arbitrary discarding of the -t component) ... this is not a popular choice since -t == FTL, however it can also provide a solution to Wheeler's delayed choice experiments ..